use the little search feature. theres plenty of info on this topic.   

Ok my motor never heats up. Barley even registers on the temp gauge. Every time I go out I close the gate valve a little more. My piping is correct up to going back to the snails. The snails are just plugged. Should I keep closing down the gate till I hit 140-160 or just leave it alone... If it ain't broke don't fix it.

Ok my motor never heats up. Barley even registers on the temp gauge. Every time I go out I close the gate valve a little more. My piping is correct up to going back to the snails. The snails are just plugged. Should I keep closing down the gate till I hit 140-160 or just leave it alone... If it ain't broke don't fix it.

does your gauge or sender work and properly grounded (some people use sealant on the thread and it doesnt make contact to work properly)?  take the wire off the sender and ground it, the gauge should do a full sweep.

usually if you preheat thru the logs you should be at least in the 100's by the time it goes thru the block and out the thermostat housing after you've been running a while.  are you sure the snails are plugged?  water coming out of the exhaust?  take the hose off of the snail and hook a regular hose up to the snail and see if you have water coming out of the back of the boat. 

If you were plugged you would over heat.

Open the gate and run cold. Mess up with the gate and the damage will be heat related. Hot pockets are possible when closing down the gate.